Electromagnetic identification label for anti-counterfeiting, authentication, and tamper-protection

ABSTRACT

A radio frequency identification label is comprised of a tag circuit  310  electrically coupled to a defined marker region  330  such that the information generated by the tag circuit is dependent on the electronic properties of the marker region  330 . The ID information conveyed to an external tag reader is thus a combination of fixed data intrinic to the tag circuit  310  plus a portion of data that is dependent on the electronic properties of the marker region. The marker region  330  can be comprised of various materials with complex structure, such as woven cloth or printed electrically conductive inks, such that the ID code transmitted by the label is thus more difficult to reproduce or to counterfeit. In addition, the marker region  330  can also be arranged to have electrical coupling to the object onto which the label is affixed, thus creating an electronic ID code that is also dependent on the electronic properties of the tagged object itself.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based on provisional application titled“Electromagnetic Identification label for Anti-Counterfeiting,Authentication, and Tamper Protection”, application No. 60/309,394,filed Aug. 1, 2001.

BACKGROUND OF INVENTION

Field of the Invention

The present invention relates in general to methods, devices and systemsfor electromagnetic identification, and in particular, toelectromagnetic identification labels and systems foranti-counterfeiting, authentication and tamper-protection.

Various techniques and methods have been used to prevent thecounterfeiting of products and provide a means of authentication. Copyprotection and authentication methods have included printing or stampingmicroscopic features that are difficult to reproduce, such as opticalholograms (for example, U.S. Pat. No. 5,729,365). Other methods haveemployed the use of detectable chemical or biological compounds such asmonoclonal antibodies. Yet other methods have made use of materials andinks that exhibit a detectable visual response when subject to a uniquephysical stimulus, such as fluorescent dye or thermochromic ink (forexample, U.S. Pat. No. 6,264,107). An undesirable feature of themajority of these methods is that they either require line-of-sight orrequire the use of relatively expensive and complex scanner hardware.

Rather than marking the object or article directly, it is commonpractice to affix to the object a label containing the aforementionedphysical properties for anti-counterfeiting and authentication. Examplesof the use of labels for these purposes can be found in a wide range ofitems and products, including important documents, photographic film,audio/video tapes, designer jeans, expensive bottles of wine, designerathletic shoes, jewelry and other luxury items. Once again, the functionof these labels generally rely on optical means of detection (forexample, U.S. Pat. No. 4,558,318). The use of electromagnetic tags ormarkers for anti-counterfeiting, authentication and tamper-protection isALSO known in the art. The basic elements of an electromagnetic taggingsystem are shown in FIG. 2. The radio-frequency id tag or label isaffixed or embedded in an object. The object can then be scanned by areader device that can ascertain the id code of the tag and compare itto a known value in a database (such as that shown in U.S. Pat. No.6,201,474, for example). (An example of authentication might involvedetermining which of two luxury watches belongs to a given customer. Anexample of anti-counterfeiting might involve determining whether aparticular example of a watch is genuine, or a copy.) A primaryadvantage of electromagnetic id labels is that line-of-sight is notrequired and the electronic scanner devices do not require complexelectronic hardware.

The simplest form of electromagnetic tags to not provide anyidentification (ID) information, but simply provide a detectable signalcommonly used in retail antitheft systems (U.S. Pat. No. 4,694,283, forexample). Conventional electromagnetic id tags can be chip-based or“chipless”. As a general matter, the information contained in chip-basedtags is encoded via digital modulation of the RF signal by theelectronic chip (U.S. Pat. No. 5,347,263, for example), while theinformation contained in chipless tags is encoded in analog signals suchas frequency resonance peaks which can then be translated into a binarycode (e.g., U.S. Pat. No. 5,444,223). Implementations that combine bothchip-based and chipless signals are also possible (see, e.g. U.S. Pat.No. 6,232,870).

For both chip-based and chipless electromagnetic tag labels, the signalor data produced by the label is pre-programmed and fixed, set either bythe data in the chip or set by the physical geometry and mechanicalproperties of the tag elements. While these fixed-data tags have enabledsome increase in security by assigning a unique serial number to theobject, there exists a continuing need for more secure ways to mark andidentify products, in a “strong” manner, for identification,authentication and anti-counterfeiting.

SUMMARY OF INVENTION

The present invention is an electromagnetic ID label, comprising a tagcircuit (chip-based or chipless) plus inlet, that provides additionalsecurity for article authentication and anti-counterfeitingapplications. Here, the term inlet is used to describe the labelsubstrate as well as a defined marker region that is electricallycoupled to the tag circuit.

Compared to existing radio-frequency ID labels, additional security isachieved by an additional data field that is not entirely fixed orpre-programmed, but which is instead based on a variable, physical,sensor-derived input, which could even be random in nature. Thephysically-derived data can be a result of a physical properties of theinlet or the physical properties of the article onto which the label isaffixed.

While the data field or ID code of the tag is a function of physicalproperties external to the tag, upon affixing the tag to the inletand/or to the article, the data field or ID code of the tag is no longervariable but becomes fixed and static as set by the electronic materialproperties of the inlet and/or article. This is an important distinctionbetween the present invention and other forms of electromagnetic tagsused to remotely monitor a dynamically changing physical parameter, suchas temperature or pressure (see for example, U.S. Pat. Nos. 5,227,798and 6,255,940).

The invention includes methods, devices and systems in whichauthentication and/or identification information is a function of thephysical properties of either the article to be authenticated, of theinlet affixed thereto (or embedded therein), or a combination of both.

Greater security is derived from the fact that the identification (ID)string generated by the tag is a complex function, i.e., a combinationof a “pre-programmed” ID data field plus the physical propertiesexternal to the tag. This produces a more secure means of authenticatingthe article and a more robust means against counterfeiting. Since thecomplete id data code relies on the physical connection for the tag tothe inlet and/or article, physical tampering of the label that disturbsthe connections between the tag, inlet, and article can also bedetected.

In accordance with the invention, the selected physical properties thatdetermine the tag's complete ID code should be (1) representative (ofthe object or article); and (2) persistent. Ideally, if the externallysensed physical properties are derived from a complex geometry, or anon-obvious manufacturing process, an additional measure of security isachieved against counterfeiting simply due to the unique nature of thephysical structure and the challenge of reproducing it. Depending on howthe “marker” region of the label is created, it can be quite difficultor substantially impossible to duplicate the marker region'sspatially-varying electrical properties without knowledge of the recipe,even if the would-be counterfeiter happens to possess the necessary rawmaterials.

Embodiments of the present invention include but are not limited to thefollowing: conventional inductively-coupled RFID (see, e.g., U.S. Pat.No. 5,347,263), capacitively-coupled RFID (see, e.g., U.S. Pat. No.6,107,920), backscatter modulation tags (see, e.g., U.S. Pat. No.6,100,804) as well as chipless tags. The substrate material onto whichthe tag circuit is placed can be paper, plastic, or cloth (see, e.g.,U.S. Pat. No. 5,508,684).

Examples of embodiments of the invention include a matrix ofelectrically-conductive fibers in a paper, or woven into a cloth, theresistivity of which can be measured and used to generate the “variable”portion of an ID string. Thus, examples of parameters of an object thatare useful in connection with the present invention include electricalconductivity, dielectric permittivity, and magnetic permeability. Theseparameters, in turn, can be a function of the substrate's composition,geometry, manufacture, process or subsequent treatment (e.g.,heat-treating, annealing, etc.).

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram illustrating the conceptual basis of thepresent invention.

FIG. 2 is a schematic diagram depicting a typical ID (identification)system utilizing the present invention.

FIGS. 3A and 3B are schematic diagrams illustrating other embodiments ofthe invention.

FIGS. 4A and 4B depict chip-based RFID embodiments of the invention(capacitive and inductive, respectively).

DETAILED DESCRIPTION

FIG. 1 is a schematic diagram illustrating the conceptual basis of thepresent invention, as implemented in either digital (chip-based) oranalog (“chipless”) tags. (Examples of digital tags include “smart”access-control cards, commonly used to enter a secure building or lockedgate. Examples of analog tags include chipless multi-resonant anti-thefttags used in retail environments) As indicated in FIG. 1, conventionaltags generate only a fixed or “programmed” ID string (i.e., the firstportion of the ID string shown in FIG. 1). An electronic label inaccordance with the present invention, however, would produce a modifiedID signal that is based not only on programmed information intrinsic tothe tag circuit, but also on a quality or physical property of eitherthe label or the object. Therefore, the combination of fixed data in thetag, plus the externally derived physical sensor data, forms a uniqueidentifier code for the tagged object. As shown in FIG. 1, in the caseof a chinless tag, this code is represented in the frequency-domain asone or more modified resonant frequency peaks; and in the case of achip-based tag, this code is represented in the time-domain as one ormore modified bit sequences output from the chip. Furthermore, in thecase of a digital chip-based tag, an additional level of security canalso be gained by encrypting the ID code with an encryption function F,such that the function F is also dependent on the externally-derivedphysical sensor data.

FIG. 2 shows a typical ID system using the invention, where the tag canbe either chip-based (digital) or chipless (analog). As depicted in FIG.2, the system would include a tag circuit 220, an “inlet” 230, a reader210 and an object 240. The “inlet” is a material or substrate onto whichthe tag is affixed. The inlet could be paper plus adhesive, cloth, orother suitable material. (As used in this document, the inlet plus thetag circuit constitutes an ID “label”.) The reader's function is tointerpret the electromagnetic signals produced by the tag and translatethem into a string of information. The structure and operation of suchreaders is known in the relevant area of electromagnetic taggingtechnology. (For example, suitable readers are discussed in theabove-referenced patents.)

Other, general embodiments of the invention are depicted in FIGS. 3A and3B, with the antenna elements omitted for clarity. In the embodimentshown in FIG. 3A the physical properties (and thus the correspondingsensor portion of the ID string) are derived from the marker region 330on the inlet 320 and thus independent of the object. For example, a“smart label” manufacturer can combine a radio-frequency IC chipcontaining sensor inputs, with a custom-manufactured inlet, and theinlet can contain special physical properties making it difficult toreproduce. By way of further example, the marker region 330 can becomprised of random patterns of conductive fibers, printed patterns ofconductive inks, or the inlet could be woven from a random network ofconductive fibers. This renders the smart label more difficult tocounterfeit. This embodiment would be suitable for labels for designergoods, such as leather goods, athletic shoes, fashion clothing, textilesand the like. A more detailed illustration of inlet 320 is shown inFIGS. 4A and 48, for the case of a chip-based label.

A further embodiment shown in FIG. 3B extends the concept of the FIG. 3a to include sensing of the physical properties of the tagged objectitself. As shown in FIG. 3B, one can create an inlet such that uponplacing it on the object, the tag circuit 310 has some means of sensingthe electromagnetic properties of the object via direct or indirectelectrical connection 350. Thus, the electromagnetic properties of theobject are coupled to the label. This can be accomplished through eitherdirect electrical connection to the object (such as by electricallyconductive adhesive), or by capacitive or inductive coupling to theobject. The properties of the object itself are now incorporated intothe ID of the label, thus achieving a unique identifier, not only forthe label, but also for the combination of label and the object.

The embodiment of FIG. 3B can be used in a variety of settings,including, for example, for authenticating bottles of wine. In such anexample, the label can be placed in the cork, such that the electricalproperties of the wine can be part of the unique identifier. This systemcould also be used to authenticate the quality of the wine. In addition,if the label is coupled to the wine bottle seal, it can also detect ifthe seal has been broken, thus providing a means of tamper protectionand ensuring seal integrity. This same technology can be applied toother types of containers and other materials such as pharmaceuticalcompounds or biological substances.

FIGS. 4A and 4B provide detail of a chip-based radio-frequency ID (RFID)embodiments; one capacitive and one inductive. In this case, it is notedthat chip-based tags typically require electrical power for an externalsource. As shown in FIGS. 4A and 4B, therefore, antenna elements 420,440 must also be included to provide power to the chip as well as tocouple data to and from the tag reader. Antenna element 420 is a anelectrically conducting patch that is suitable for capacitive couplingto the reader, and antenna element 440 is a coil which is suitable forinductive coupling to the reader. Such antenna structures are known inthe art, and examples are described in the above-listed patents. Thenovel aspects of FIGS. 4A and 4B however, include the combination ofmarker regions 430 and the tag circuit 410.

1. A radio frequency identification label comprising: a substratematerial layer; and a tag circuit capable of producing anelectromagnetic signal containing information; and at least one antennaelement for coupling the tag circuit to an external tag reader device;and at least one defined marker region of electrically conductivematerial that is distinct from the antenna elements and electricallycoupled to the tag circuit; and the tag circuit arranged such that allor part of its information is dependent on the electrical properties ofthe marker region.
 2. The radio frequency label of claim 1, wherein thetag circuit is a digital electronic integrated circuit.
 3. The radiofrequency label of claim 1, wherein the tag circuit is a circuit iscomprised of polymer-based transistors and passive components.
 4. Theradio frequency label of claim 1, wherein the tag circuit is a chiplesscircuit comprised of one or more electrically resonant circuitsconsisting of a planar metal coil and distributed capacitance.
 5. Theradio frequency label of claim 1, wherein the substrate layer iscomprised of woven cloth or threads.
 6. The radio frequency label ofclaim 1, wherein the marker region is comprised of woven cloth orthreads.
 7. The radio frequency label of claim 2, wherein the label isinductively-coupled to the tag reader device.
 8. The radio frequencylabel of claim 2, wherein the label is capacitively-coupled to the tagreader device.
 9. The radio frequency label of claim 3, wherein thelabel is inductively-coupled to the tag reader device.
 10. The radiofrequency label of claim 3, wherein the label is capacitively-coupled tothe tag reader device.
 11. The radio frequency label of claim 7, whereinat least one marker region is also electrically coupled to the objectonto which the label is affixed.
 12. The radio frequency label of claim8, wherein at least one marker region is also electrically coupled tothe object onto which the label is affixed.
 13. The radio frequencylabel of claim 9, wherein at least one marker region is alsoelectrically coupled to the object onto which the label is affixed. 14.The radio frequency label of claim 10, wherein at least one markerregion is also electrically coupled to the object onto which the labelis affixed.
 15. The radio frequency label of claim 4, wherein at leastone marker region is also electrically coupled to the object onto whichthe label is affixed.
 16. The radio frequency label of claim 7, whereinthe marker region is comprised of a printed pattern of electricallyconductive ink.
 17. The radio frequency label of claim 8, wherein themarker region is comprised of a printed pattern of electricallyconductive ink.
 18. The radio frequency label of claim 9, wherein themarker region is comprised of a printed pattern of electricallyconductive ink.
 19. The radio frequency label of claim 10, wherein themarker region is comprised of a printed pattern of electricallyconductive ink.
 20. The radio frequency label of claim 2, wherein theinformation generated by the tag circuit is encrypted by a mathematicalfunction that is dependent on the electrical properties of the markerregion.
 21. The radio frequency label of claim 2, wherein theinformation generated by the tag circuit is encrypted by a mathematicalfunction that is dependent on a parameter derived from the electricalproperties of the marker region.
 22. The radio frequency label of claim7, wherein at least one marker region is also electrically coupled tothe object onto which the label is affixed, wherein the informationtransmitted by the radio frequency identification label is alsodependent on the electrical properties of the object.
 23. The radiofrequency label of claim 8, wherein at least one marker region is alsoelectrically coupled to the object onto which the label is affixed,wherein the information transmitted by the radio frequencyidentification label is also dependent on the electrical properties ofthe object.
 24. The radio frequency label of claim 9, wherein at leastone marker region is also electrically coupled to the object onto whichthe label is affixed, wherein the information transmitted by the radiofrequency identification label is also dependent on the electricalproperties of the object.
 25. The radio frequency label of claim 10,wherein at least one marker region is also electrically coupled to theobject onto which the label is affixed, wherein the informationtransmitted by the radio frequency identification label is alsodependent on the electrical properties of the object.
 26. The radiofrequency label of claim 4, wherein at least one marker region is alsoelectrically coupled to the object onto which the label is affixed,wherein the information transmitted by the radio frequencyidentification label is also dependent on the electrical properties ofthe object.